Hydrodeoxygenation of a bio-oil model compound derived from woody biomass using spray-pyrolysis-derived spherical γ-Al2O3-SiO2 catalysts

In this study, spherical gamma-Al2O3-SiO2 catalysts with various Al/Si ratios were prepared by combining the sol-gel and spray pyrolysis (SP) methods. The effectiveness of the product catalysts was then tested via the hydrodeoxygenation (HDO) of guaiacol, a model compound of bio-oil obtained from the pyrolysis of lignocellulosic biomass. Our results showed that the gamma-Al2O3-SiO2 catalyst with a 50:50 Al/Si ratio after calcination at 450 degrees C exhibited the highest guaiacol conversion (81.79%) at a reaction temperature of 300 degrees C, atmospheric pressure, and a weight hourly space velocity (WHSV) of 6.5 h(-1). During guaiacol HDO, the carbon-oxygen cleavage and methyl group transfer reactions occurred on the gamma-Al2O3-SiO2 catalyst, which converted the guaiacol into the respective deoxygenated products, including 2,6-xylenol, 2,3,5,6-tetramethyl phenol, pentamethyl benzene, and hexamethyl benzene. The reaction pathways for the conversion of guaiacol HDO were also proposed in this study. (C) 2020 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.